Pumping unit and power machine



May 20, 1941.

B. S. LIGHTFQOT PUMPING UNIT AND POWER MACHINE Filed Aug. 24, 1939 4Sheets-Sheet 1 May 20, 1941. B. s. LIGHTFOOT 2,242,252

PUMPING UNIT AND POWER MACHINE Filed Aug. 24, 1939 4 Sheets- Sheet 2INVENTOR.

' ATTORNEY.

May 20, 1941.

B. s. 'LIGHTFOOT 2,242,252

PUMPING UNIT AND POWER MACHINE Filed Aug. 2 1, 1939 4 Sheets-Sheet 5INVENTOR.

y 20, 1941- -B. s. LIGHTFOOT 2,242,252

PUMPING UNIT AND POWER MACHINE Filed Aug. 24, 1939 4 Sheets-Sheet 4 INVENTOR.

Patented May 20,1941

UNITED STATES PATENT OFFICE PUMZPIN G UNIT AND POWER MACHINE Byron S.Lightfoot, Dallas, Tex.,assignor.offonehalf to R. E. Harding,Raymondvillc, Tex:

Application August 24, 1939, Serial'No. '291,642

2 Claims.

Thisinvention relates to powermachines for pumping wells or forperforming work of a similar nature to which it may be applied.

An object of this invention is to provide a jack wherein the walkingbeam will be substantially balanced so as to permit the use ofa..smaller power source.

Another object of this invention is to provide a jack whichincludesmeans for conserving the power, the. device including a walking beamconnected to a power source and a linkage connected to the beam and thepower source for utilizing the downward thrust at the working end of thebeam to effect a balance at the driving end of the beam.

The machine is of few parts and its operation is without vibration, itsmovement being smooth, devoid of jerks or jars and of a flowing nature.It can be thus operated at a high rate of speed Without danger ofbreakage.

The invention will be readily understood from a perusal of the followingdetailed description, taken in connection with the accompanyingdrawings:

Figure 1 is a side elevational view of the machine, partly broken away;

Figure 2 is a side elevational View of the machine the view being takenfrom the side opposite to that of Figure 1; the motor not shown;

Figure 3 is a top plan view of the machine taken on Figure 1 and partlybroken away;

Figure 4 is a sectional detail view of Figure 3, the view being had onthe line 44 of said figure;

Figure 5 is an edge view of Figure 4, taken from the left in thedrawings; and

Figure 6 is a detail view of one end of the lifting lever and horsehead.

In the construction and carrying out of the invention there is employeda suitable frame with a derrick-like portion I of suitable height, asillustrated in Figures 1 and 2. The frame includes sides 2 with legs 3,resting on any suitable support 4. Motive power is supplied preferablyby a motor 5 or other means.

In Figure 1 and at approximately the center of the frame is mounted apulley wheel 6 on a shaft 7 and connected to the shaft pulley 8 of themotor by a belt drive 9. The shaft 7 is made to rotate on bearings ID inthe sides of the frame as shown. The rotation of the pulley wheel 6 isimparted to the operating parts of the machine by means of a pulley llcarried on the opposite end of the shaft 1, the belt drive l2 and asecond pulley wheel [3 in: connection with a crank shaft assembly whichwill be described hereinafter.

Atthej highest point of the derrick-like portion of the frame at l arebearing blocks I 4 with bearings for supporting a shaft or king pin Bandon thisking pin or shaft is mounted an L-shaped elementconsisting ofacentral head or block I! with an extension IB. Extending downwardlyfrom the block I! is ,a leg Hi, the block, extension and leg l9,comprising a rocker arm and so termed throughout the specification.

As carried, out in the construction of the machine, there is alsoprovided a lifting beam 20 on one end of Whichis adjustably mounted anelement =2I, commonly knownas a horse-head. The horse-head is curved inthe familiar manner and likewise grooved as indicated at 22 toaccommodate the reception of acable indicated by the broken lines at'23, and leading to a well. This end'of thelifting beam 20, however, maybe connected to? any object. to which the machine may be used forutilization of its power.

The rocker arm is pivotally connected to the beam 20 by means of a pairof links 26, the links having circular bearing heads as shown for thepins 28 and 29. The pin 28 passes through the lifting beam 20 and isconnected to the lower ends of the links 26, thus pivoting the links tothe beam. The assembly of parts is completed at this point of themachine by the provision of a pair of guide links 30, the ends 3| ofthese links being pivotally connected to the pin 28 and their oppositeends 3l-a pivoted to the circular bearing blocks 32.

The opposite end of the lifting beam 20 is pivotally connected by a pin20a to an element 33 which may be termed a connecting rod, whereby powerfrom the motor acting through the pulley wheel 6, shaft 1, pulley H andthe pulley wheel l3, in connection with the belt drives 9 and I2,actuates the lifting beam 20.

The crank shaft assembly comprises a member 34 of substantial L-shape,one end 35 of which is pivoted to one end of the link 33 by a pin 33a,as shown by Figures 4 and 5, also Figure 2. A companion piece or link 36is next provided, the piece or link 36 being pivoted to a stud shaft 31on which the pulley wheel I3 is mounted.

Carried on the lifting beam 20 is a member 38 which is for the purposeof adding more weight by shifting the member laterally when required.However, the weight is not absolutely necessary to the operation of themachine.

A balancing link 39 has one end 40 pivotally connected by a pin 4|through any of the apertures 42 in the leg l9 of the rocker armaccording to the adjustment required and as will be clear from Figures 1and 2. The opposite end of the balancing link 39 is pivoted by a pin 42to the crank shaft assembly member 34, which member provides a balancingthrow. Finally there is provided a link 44 which has one end pivoted tothe balancing link 39 and its opposite end seated in a bearing 45 in oneside 2 of the frame.

In the operation of the machine, when the load is applied on or to thelifting head 2|, the connecting rod 33 moves downwardly, thus raisingthe load, and pressure is exerted on and at the pivot 28. The appliedforce then passes through the link 26 to the extension I8 of the rockerarm block H to the pivot or pin 15, down the leg 19 of the rocker arm tothe pivot 'or pin 4|, thence through the lever 39 to the crank shaftassembly member 34. At this point of the operation'of the machine, thetotal pressure is being exerted along the lifting beam 20.

During the upward movement of the head 2| caused by the downstroke ofthe crank 34 the inner or driving end of the beam or lever 20 is beingdrawn downwardly by the link 33. At this time the secondary crank pin 42will apply a driving force to the balancing lever 39 which will rock thebell-crank l'|--l9 to apply a similar downward thrust to the beam orlever 20 through the link 26.

As the head 2| moves downwardly the weight of the tools will tend topull the inner or driving end of the beam upwardly. The positioning ofthe pivot 28 between the pivot 20 and the beam fulcrum will permittransfer of the downward pull of the head 2| from the pivot 28 throughthe link 26, and bell crank "-19 to the balancing lever 39. This willefiect a closer balance between the movements of the beam 20 than ispossible by the use of a counterweight, as the thrust of the lever 39 onthe downstroke of the head 2| will be proportionate to the weight of theload.

While the invention discloses a practical working embodiment of themachine, it is to be understood that various alterations, changes andmodifications may be made in keeping with the intent and motive thereof,and which would be within the scope and meaning of the appended claims.

What is claimed is:

1. A pumping jack comprising a frame, a crankshaft rotatably carried bythe frame, said crankshaft including an auxiliary crank pin and a maincrank pin, a walking beam rockably carried by said frame, a pitmanconnecting the inner end of said beam to said main crank pin, a liftinghead carried by the outer end of said beam, a bell-crank rockablycarried by said frame, means connecting one arm of said bell-crank tosaid beam at a point between the fulcrum of said beam and said pitman,and a balancing link connected at one end to the other arm of saidbellcrank and connected at the opposite end to said auxiliary crank pin.

2. A pumping jack comprising a frame, a crankshaft rotatably carried bythe frame, said crankshaft including an auxiliary crank pin and a maincrank pin, a walking beam rockably carried by said frame, a pitmanconnecting the inner end of said beam to said main crank pin, a liftinghead carried by the outer end of said beam, 8, bellcrank rockablycarried by said frame, means connecting one arm of said bell crank tosaid beam at a point between the fulcrum of said beam and said pitman, abalancing link connected at one end to the other arm of said bell crankand connected at the opposite end to said auxiliary crank pin, and adrive wheel carried by said crank shaft.

BYRON S. LIGHTFOOT.

